Hermetic compressor

ABSTRACT

A hermetic compressor comprising a discharge muffler. The discharge muffler includes a muffler body dented in a cylinder block and a muffler cover covering the muffler body. The muffler cover has an integral center fixing protrusion  61  extending toward the muffler body, while the muffler body has a fixing recess to permit insertion and fixation of the fixing protrusion.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 2004-51096, filed on Jul. 1, 2004 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a hermetic compressor, and, more particularly, to a hermetic compressor having a discharge muffler capable of attenuating noise generated when a compressed refrigerant is discharged to the outside.

2. Description of the Related Art

In general, a hermetic compressor is designed to suction a refrigerant into a hermetic casing thereof to compress it, and discharge the compressed refrigerant to the outside. Such a hermetic compressor comprises a compressing unit to compress the refrigerant and a driving unit to drive the compressing unit.

The compressing unit is disposed inside the hermetic casing, and includes a cylinder block defining a compression chamber, and a piston reciprocating inside the compression chamber upon receiving power transmitted from the driving unit. A cylinder head is disposed at one side of the cylinder block and is formed with a suction chamber and a discharge chamber, which communicate with the outside.

A valve unit is provided between the cylinder block and the cylinder head in order to permit selective communication between the suction chamber and the compression chamber or between the discharge chamber and the compression chamber.

In order to attenuate pulsation of the refrigerant being discharged from the discharge chamber, a pair of discharge mufflers are provided at both ends of the cylinder block, respectively. A respective one of the discharge mufflers has a muffler body defined in the cylinder block, and a muffler cover to cover the muffler body. The muffler cover is coupled to the muffler body as a fastening bolt penetrates through the muffler cover and is fastened to the muffler body. A washer is interposed between a head portion of the fastening bolt and the muffler cover in order to increase fastening force of the bolt.

However, the typical hermetic compressor has a problem in that it should have several parts, such as the fastening bolt and the washer, for the coupling of the muffler body and the muffler cover, resulting in a complicated manufacturing process and high manufacturing cost of the compressor.

Further, the fastening bolt and the washer may generate debris as a result of wear, resulting in a deterioration in the quality of the compressor.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above mentioned problems, and an aspect of the invention is to provide a hermetic compressor which can eliminate the need for additional parts, such as a fastening bolt and washer, required to couple a muffler body with a muffler cover to assemble a discharge muffler, thereby simplifying the overall manufacturing process and reducing the manufacturing cost of the compressor.

In accordance with an aspect, the present invention provides a hermetic compressor comprising a cylinder block defining a compression chamber, a piston reciprocating inside the compression chamber to compress a refrigerant, and a discharge muffler configured to receive the refrigerant compressed in the compression chamber, the discharge muffler including a muffler body defined in the cylinder block and a muffler cover to cover the muffler body, the muffler cover having an integral fixing protrusion to be affixed relative to a bottom surface of the muffler body.

The muffler body may have a fixing recess formed at the bottom surface thereof to permit the fixing protrusion of the muffler cover to be fixedly inserted therein.

The muffler body may further have an annular raised rim portion extending upward from the bottom surface of the muffler body toward the muffler cover to define the fixing recess.

A gasket may be interposed between the muffler cover and the muffler body to ensure sufficient sealing therebewteen.

The compressor may further comprise a discharge tube to discharge the refrigerant from the interior of the discharge muffler to the outside, and the discharge tube may be mounted in a fitting bore perforated through the fixing protrusion of the muffler cover.

The discharge tube may have a first communication hole at a circumferential position thereof, and the fixing protrusion may have a second communication hole at a circumferential position thereof corresponding to the first communication hole, for the communication between the discharge tube and the interior of the discharge muffler.

The muffler cover may further have a pair of partitions extending toward the bottom surface of the muffler body, the partitions being spaced apart from the bottom surface of the muffler body.

The partitions may be positioned at opposite sides of the fixing protrusion.

Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will become apparent and more easily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a side sectional view of a hermetic compressor in accordance with the present invention;

FIG. 2 is a plan view of the hermetic compressor shown in FIG. 1;

FIG. 3 is a sectional view of a discharge muffler provided in the hermetic compressor in accordance with a first embodiment of the present invention;

FIG. 4 is a sectional view of a discharge muffler provided in the hermetic compressor in accordance with a second embodiment of the present invention;

FIG. 5 is a sectional view of a discharge muffler provided in the hermetic compressor in accordance with a third embodiment of the present invention; and

FIG. 6 is a sectional view of a discharge muffler provided in the hermetic compressor in accordance with a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the embodiment of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

FIG. 1 is a side sectional view of a hermetic compressor in accordance with the present invention. Referring to FIG. 1, the hermetic compressor of the present invention comprises a compressing unit 20 disposed inside a hermetic casing 10 to compress a refrigerant, and a driving unit 30 to generate power required to drive the compressing unit 20.

The compressing unit 20 includes a cylinder block 21 internally defining a compression chamber 21 a, and a piston 22 reciprocating inside the compression chamber 21 a so as to suction, compress and discharge the refrigerant. A cylinder head 23 is disposed at one end of the cylinder block 21 to face each other. The cylinder head 23 internally defines a suction chamber 23 a and a discharge chamber 23 b. A valve unit 24 is interposed between the cylinder block 21 and the cylinder head 23 so as to selectively communicate the suction chamber 23 a or the discharge chamber 23 b with the compression chamber 21 a.

The driving unit 30 operates to reciprocate the piston 22, thereby permitting the refrigerant to be compressed inside the compressing unit 20. The driving unit 30 includes a stator 31 fixedly disposed inside the hermetic casing 10, and a rotor 32 inwardly spaced apart from the stator 31 to electromagnetically interact with the stator 31. A rotating shaft 33 is coupled in the center of the rotor 32 to rotate simultaneously with the rotor 32. An end of the rotating shaft 33 is coupled to one end of a connecting rod 34 to permit rotation of the connecting rod 34. The rotation of the connecting rod 34 causes the other end thereof to linearly reciprocate to thereby move the piston 22 forward or backward.

FIGS. 2 and 3 are a plan view and a sectional view illustrating a discharge muffler provided in the hermetic compressor in accordance with a first embodiment of the present invention. Referring to FIGS. 2 and 3, the discharge muffler 40 according to the first embodiment of the present invention is provided at at least one of both ends of the cylinder block 21 and is adapted to attenuate noise of the refrigerant being discharged out of the compressor. The discharge muffler 40 has a dented muffler body 50 defined in the cylinder block 21 and a muffler cover 60 to cover the muffler body 50.

The muffler body 50 has an inlet 51 to permit introduction of the refrigerant into the discharge muffler 40. The inlet 51 communicates with a guide channel 25 which is perforated through the cylinder block 21 to guide the refrigerant from the compression chamber 21 a into the discharge muffler 40.

The muffler body 50 further has an outlet 52 positioned opposite to the inlet 51 to permit discharge of the refrigerant from the discharge muffler 40. A seating groove 53 is defined at an upper end of the muffler body 50 for the seating of the muffler cover 60.

When the muffler cover 60 covers the muffler body 50, it defines a space to attenuate pulsation of the refrigerant. In the present embodiment, the muffler cover 60 has a center fixing protrusion 61 extending from a lower surface thereof toward a bottom surface of the muffler body 60. The fixing protrusion 61 is affixed relative to the bottom surface of the muffler body 50 to securely couple the muffler cover 60 with the muffler body 50. In this case, the bottom surface of the muffler body 50 is formed with a fixing recess 54 to permit an end region of the fixing protrusion 61 to be inserted and fixed therein. In order to ensure sufficient fitting of the fixing protrusion 61 in the fixing recess 54, an annular raised rim portion 55 is also formed at the bottom surface of the muffler body 50 to define the fixing recess 54. The annular raised rim portion 55 protrudes upward by a distance suitable to provide the fixing recess 54 with a sufficient depth.

In order to improve sealing efficiency between the coupled muffler cover 60 and muffler body 50, a gasket 70 is interposed between the muffler cover 60 and the muffler body 50.

Meanwhile, the fixing protrusion 61 may be forcibly press-fitted into the fixing recess 54, or may be screwed into the fixing recess 54 as is shown in FIG. 4. In the latter case, the fixing protrusion 61 is provided at an outer circumference thereof with a first screw portion 61 a, while the fixing recess 54 is provided at an inner circumference thereof with a second screw portion 54 a corresponding to the first screw portion 61 a.

Referring to FIG. 5, a discharge tube 80 is mounted in the muffler cover 60 in order to permit the refrigerant, which has been reduced in pulsation thereof within the discharge muffler 40, to be discharged out of the compressor via the discharge tube 80. In this case, the discharge tube 80 is fitted in an elongated fitting bore 62 which extends, starting from an upper end of the muffler cover 60, through the fixing protrusion 61. For the communication between the discharge tube 80 and the interior of the discharge muffler 40, the discharge tube 80 has a first communication hole 81 at a circumferential position thereof, and the fixing protrusion 61 has a second communication hole 63 at a circumferential position thereof corresponding to the first communication hole 81.

Referring to FIG. 6, the muffler cover 60 may further have a pair of partitions 64 extending downward from the lower surface of the muffler cover 60 toward the bottom surface of the muffler body 50. The partitions 64 are positioned at opposite sides of the fixing protrusion 61, and are spaced apart at their distal ends from the bottom surface of the muffler body 50. Such an arrangement permits the refrigerant to be compressed and diffused while passing through a space defined between the distal ends of the partitions 64 and the bottom surface of the muffler body 50, thereby effectively attenuating refrigerant pulsation.

Now, the general operation of the hermetic compressor according to the present invention will be explained.

When power is applied to the driving unit 30, the rotor 32 rotates simultaneously with the rotating shaft 33. The rotation of the rotating shaft 33 causes the piston 22 to reciprocate inside the compression chamber 21 a to thereby allow the refrigerant to be suctioned from the suction chamber 23 a of the cylinder head 23 into the compression chamber 21 a and be compressed in the compression chamber 21 a. After that, the compressed refrigerant is discharged into the discharge chamber 23 b of the cylinder head 23 via the valve unit 24 according to reciprocation of the piston 22.

In succession, the refrigerant discharged into the discharge chamber 23 b is introduced into the inlet 51 of the muffler body 50 via the guide channel 25 defined in the cylinder block 21. Thereby, within the discharge muffler 40, which is formed by securely coupling the muffler body 50 with the muffler cover 60 in the present invention, the refrigerant can undergo attenuation in the pulsation thereof and is finally discharged out of the compressor.

As is apparent from the above description, a hermetic compressor according to the present invention comprises a discharge muffler in which a muffler cover is securely coupled to a muffler body via a fixing protrusion integrally formed at the muffler cover. With such a configuration, there is no need to provide additional parts, such as bolts and washers, required to couple the muffler cover with the muffler body. This has the effect of simplifying the overall manufacturing process and reducing manufacturing costs of the compressor.

Although an embodiment of the present invention has been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. 

1. A hermetic compressor comprising a cylinder block defining a compression chamber, a piston reciprocating inside the compression chamber to compress a refrigerant, and a discharge muffler configured to receive the refrigerant compressed in the compression chamber, wherein the discharge muffler includes a muffler body defined in the cylinder block, and a muffler cover to cover the muffler body, wherein the muffler cover has an integral fixing protrusion to be affixed relative to a bottom surface of the muffler body.
 2. The compressor according to claim 1, wherein the muffler body has a fixing recess formed at the bottom surface thereof to permit the fixing protrusion of the muffler cover to be fixedly inserted therein.
 3. The compressor according to claim 2, wherein the muffler body further has an annular raised rim portion extending upward from the bottom surface of the muffler body toward the muffler cover to define the fixing recess.
 4. The compressor according to claim 1, wherein a gasket is interposed between the muffler cover and the muffler body to ensure sufficient sealing therebewteen.
 5. The compressor according to claim 1, further comprising a discharge tube to discharge the refrigerant from the interior of the discharge muffler to the outside, wherein the discharge tube is mounted in a fitting bore perforated through the fixing protrusion of the muffler cover.
 6. The compressor according to claim 5, wherein the discharge tube has a first communication hole at a circumferential position thereof, and the fixing protrusion has a second communication hole at a circumferential position thereof corresponding to the first communication hole, for the communication between the discharge tube and the interior of the discharge muffler.
 7. The compressor according to claim 1, wherein the muffler cover is further provided with a pair of partitions extending toward the bottom surface of the muffler body, the partitions being spaced apart from the bottom surface of the muffler body.
 8. The compressor according to claim 7, wherein the partitions are positioned at opposite sides of the fixing protrusion. 